High Performance Liquid Cromatography Research Articles

İNEK, KOYUN VE KEÇİ SÜTÜNDEN ÜRETİLEN KAYMAKLARIN BAZI KARBONİL BİLEŞİKLERİ, SERBEST YAĞ ASİDİ BİLEŞİMLERİ VE TOKOFEROL İÇERİKLERİ

The aim of this study is to determine the effect of cow, goat and sheep milk used in traditional clotted cream production on some properties of clotted cream. The produced clotted cream was stored during 7 days. Some chemical analyses of the clotted cream, free fatty acid composition and tocopherol contents using gas chromatography (GC) and high-performance liquid cromatography (HPLC) were determined. Saturated fatty acids were found to be the highest in sheep's clotted cream and the lowest in goat's clotted cream. Monounsaturated fatty acids were found to be higher in clotted cream produced from goat's milk. Eicosapentaenoic Acid (EPA) and docosanhexaenoic acid (DHA) and δ-tocopherol were determined only in clotted cream produced from sheep milk. The content of α-tocopherol in sheep's clotted cream and β-tocopherol in cow's clotted cream is higher than in the other clotted cream. 2-Methylbutyraldehyde was identified as the most important carbonyl component in all samples. Although all three clotted creams were quite similar in appearance and some chemical properties, it was determined that they contain significant differences in terms of carbonyl compounds, fatty acid profiles and tocopherol contents.

ANALISIS KADAR KUERSETIN PADA EKSTRAK ETANOL DAUN MIANA (Plectranthus scutellarioides (L.) R.Br.) SECARA HPLC (High Performance Liquid Chromatography)

One of the medicinal plants that people often use as a medicine is the Miana leaves (Plectranthus scutellarioides (L.) R.Br.). The Miana leaves are empirically used to treat coughs, heart disease, worm medicines, antimicrobials, antioxidants, antiseptics, bronchitis, hemorrhoids, tuberculosis, and other pharmacological activities. The miana leaves contain secondary metabolite compounds of flavonoids, steroids, tannins, and saponins. One of the most critical flavonoids is quercetin. This study aimed to determine the quercetin content of ethanol extract of miana leaves by HPLC (High Performance Liquid Cromatography). The extraction method by maceration using 96% ethanol. Determination of quercetin content in miana leaf ethanol extract by HPLC with C 18 column, maximum wavelength of 369.11 nm with mobile phase methanol : aquabides (59:41) flow rate of 1 mL/minute. The results showed retention time for quercetin as a comparison of 4,183 minutes, a sample of 4.563 minutes, and an additional sample of 4,363 minutes. The average content of quercetin in miana leaf ethanol extract was 3.122 mg/g or 0,312%.

Analysis of hydroxy-cocaine metabolites as evidence of cocaine consumption: Identification by parent ion search and quantitation by UHPLC-MS/MS in hair

Over the last decade, hair analysis has become a routine procedure in most forensic laboratories and, complementary to blood and urine, hair is a unique biological matrix which gives the opportunity to establish a temporal consumption profile. Despite hair is widely used to identify drug use, environmental contamination continues to represent a challenging factor of this procedure, especially for cocaine (COC). In the last few years several strategies have been proposed in order to distinguish between actual use and external contamination, however the commonly detected COC metabolites probably are insufficient for demonstrating cocaine use through hair testing. Thus, the aim of this study is to develop an ultra high performance liquid cromatography - tandem mass spectrometry (UHPLC-MS/MS) method able to detect and quantify hydroxy-COC metabolites, as specific markers of COC abuse, in hair samples from COC consumers, thus enabling unambiguous evidence of COC consumption. At the beginning, since no commercial reference materials were available, COC‐positive hair samples were tested using parent ion scan-based analysis to extract hydroxy COC metabolites target ions. Once identified, the reference materials were synthesized by our analytical laboratory allowing the development of the first UHPLC-MS/MS validated method to quantify p‐ and m‐isomers of hydroxy COC, as well as hydroxy benzoylecgonine (BE) and hydroxy norcocaine (NCOC). The method was successfully applied to a large number of COC-positive hair samples and introduced into a routine procedure for testing drug ingestion in order to evaluate for the first-time hydroxy metabolites of COC ranges in hair and their correlation with COC and BE.

An investigation into green coffee press cake as a renewable source of bioactive compounds

SummaryThe residual biomass of coffee, obtained after the oil extraction from coffee beans, called coffee beans residual press cake, has been attracted interest as a source of compounds with antioxidant capacity. This study investigated the effects of ethanolic and methanol‐acetone extracts of green coffee beans (GCB) and its residual press cake (GCC) on the phenolic composition and antioxidant capacity. Antioxidant capacity was assayed through five different methods (total phenolic compounds, •DPPH, ABTS, FRAP and β‐carotene bleaching assay), and the phenolic profile of the samples through High Performance Liquid Cromatography. GCB and GCC enclosed chlorogenic (55.16 and 64.96 mg g−1, respectively) and caffeic (25.07 and 44.37 mg g−1, respectively) acids as the major components, and the cake presented higher antioxidant capacity than the actual green bean. Antioxidant capacity was higher for GCC extracted with methanol and acetone. This study on the evaluation of the effects of the type of solvent on the bioactive compounds from GCB and GCC showed that this by‐product can be a source of new value‐added products, such as phenolic antioxidant adjuncts for food or pharmaceutic processing.

Ivermectin and albendazole withdrawal period in goat milk

SUMMARY Theaimthis study was to determine the excretion profile of albendazole and ivermectin residues in milk from goats submitted to antiparasitic treatment. Twenty-four Brazilianmongrel lactating and pluriparous goats, maintained extensively on native pasture were orally treatedwith albendazole or ivermectin. Milk samples were collected before and after vermifuges application, in the days 0, 2, 3 e 4 to albendazole and 0, 3, 7, 14, 21, 28, 35 and 42 to ivermectin. The vermifuges residues were detected by high performance liquid cromatography with ultravioletdetector. The amount of residues contained in themilk was decreasing in function of time. The mean daily rates of decrease of albendazole residues were 63.34%, 40.18 and 100.0%, from the 2ndto the 4thday, respectively; on the 3rdday after treatment, 50% of the samples showed concentrations ≥ 47.61 μg.mL–1, and on the 4thday, no sample had albendazole residue. The amount excreted of ivermectin was similar between the 3rdand 21stday when all samples presented values ≥ 51.90 μg.mL-1; on the 35th day, 50% of the samples showed values above of recommended levels, and on the 42nd day, no sample had detectable ivermectin residue. In conclusion, the milk of Brazilian mongrel goats treated orally with albendazole or ivermectin does not contain its respective residues in detectable amounts from the 4th and 42nddays, respectively, after antiparasitic treatment.

PP.25.08] THERAPEUTIC DRUG MONITORING IN RESISTANT HYPERTENSIVES PREVIOUSLY TREATED WITH INVASIVE APPROACHES

Objective: Renal denervation (RDN) and baroreflex activation therapy (BAT) are invasive therapeutic approaches for resistant hypertension (RH), indicated when antihypertensive drug therapy is inefficacious. Several reports have found an unsatisfactory response to these approaches; one of the factors called upon to account for the failure of these devices is the lack of therapeutic adherence. The aim of this study was to retrospectively evaluate the therapeutic adherence, using an objective assessment as the therapeutic drug monitoring (TDM), in a group of patients who have undergone invasive approach in previous years, either RDN or BAT, and correlate it with the answer to the invasive procedure. Design and method: We retrospectively analysed 12 patients with RH (9 females). Before performing invasive procedure, all patients were considered adherent according to the physician intuition and the answers given to the Morisky questionnaire. Serum TDM, by Ultra High Performance Liquid Cromatography (UHPLC) method, was done during a routine follow up visit, after at least one year from the last invasive approach. A clinical response to invasive approaches was considered as a reduction in 24 h Ambulatory Blood Pressure Monitoring (ABPM) systolic blood pressure (SBP) of at least 10 mmHg at 12 months from the procedure. Patients were considered adherents (AD) if all the prescribed drugs were found or only one was not found; patients were considered non-adherents (NAD) if none of the prescribed drugs were found. Results: 4 patients were AD and 8 NAD. In the whole sample a clinical response was found in 41% of the patients. Among AD the clinical response rate was 75%, whilst among NAD the clinical response rate dropped to 25%. No significant clinical and social differences were found between NAD and AD, but NAD had significant higher office SBP and 24 h ABPM SBP than AD (p < 0.05). Conclusions: Lack of therapeutic adherence is associated to a limited clinical efficacy of invasive approaches in apparent RH. Our data underlines the importance of adherence therapeutic evaluation before and after performing invasive procedures, whose effectiveness can be undermined by poor therapeutic adherence.

Degradation of Vancomycin Hydrochloride by Electrooxidation

Many pharmaceuticals are considered recalcitrant pollutants and represent a problem for human and animal health due to continuous contribution in the aquatic environment and the bacteria resistance development to antibiotics. Vancomycin is one of the most antibiotics administered in medicine, nevertheless, there is not much knowledge about the presence, fate and the effects of Vancomycin in the environment. The advanced oxidation techniques (AOTs) are shown as alternatives for the treatment of water and wastewater in order to degrade pollutants and contaminants. Therefore, this work is aimed to evaluate the Vancomycin degradation in an aqueous medium using electrooxidation (EO) technique and to optimize the reaction conditions. The experiments were conducted in a homemade electrochemical cell in acrylic with a working volume of 500 cm3; DSA electrodes – Dimensionally Stable Anodes (70TiO2-30RuO2) were used (effective area of work - 41.25 cm2); NaCl P.A. was used as supporting electrolyte; 130 mg L-1 of Vancomycin was used in aqueous solution. The optimization was done using central composite design (CCD) totaling 18 experiments. The evaluated factors were: interelectrodes distance (ID), applied current and supporting electrolyte concentration. All experiments were conducted for 20 minutes with sampling at 0, 1, 2, 3, 4, 5, 10 and 20 minutes. Vancomycin concentrations were determined by High Performance Liquid Cromatography with Diode-Array Detection (HPLC-DAD) (Mobile phase: phosphate buffer 0.05 mol L-1, pH 4.7: MeOH: ACN [80:15:5, v/v], Injection volume: 40 L; C18 with flow rate of 1.0 mL min-1, λ: 210 nm. The results show that the electrooxidation is effective in Vancomycin degradation, showing as an alternative to degradation of this drug. The method used obtained 100% of degradation in 2 minutes of treatment in optimum conditions: 400 mA, 3 cm interelectrodes distance and 1,100 mg L-1 NaCl.

Antioxidant Capacity, Radical Scavenging Kinetics and Phenolic Profile of Methanol Extracts of Wild Plants of Southern Sonora, Mexico

Purpose: To investigate the antioxidant and phenolic profiles of methanol extracts from Rhizophora mangle L, Krameria erecta, Lycium berlandieri Dunal, Vallesia glabra Link and Forchammeria watsonii Rose.Methods: The free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method was used for antioxidant assay of methanol plant extracts. Phenolic compounds determination was carried out by high performance liquid cromatography (HPLC) using an analytical C18 column eluting with acetonitrile on a gradient program.Results: Extract from Rhizophora mangle L and Krameria erecta displayed 5-fold higher antioxidant capacity than ascorbic acid with DPPH reduction values of 95.71 and 91 %, respectively. Anti-radical kinetic analysis and stoichiometric constant values suggest that the compounds responsible forantioxidant activity are polyphenols and flavonoids with a free or mono-substituted catechol group. Ferulic and vanillic acids had higher contents in Rhizophora mangle L (688.45 ± 18.21 and 7.13 ± 0.125mg/g, respectively) and Krameria erecta (619.92 ± 28.16 mg/g and 22.29 ± 0.72 mg/g, respectively) than the other constituents.Conclusion: Rhizophora mangle and Krameria erecta possess five times the antioxidant activity of ascorbic acid and also demonstrate high phenolic contents, which supports the beneficial properties attributed to these plants in traditional medicine, and also justifies the use of the plants as alternative medicines.Keywords: Rhizophora mangle, Krameria erecta, Ferulic acid, vanillic acid, Antioxidant capacity, Alternative medicines, Phenolics, Anti-radical kinetics

Degradación de carotenoides y capsaicina en el complejo de inclusión molecular de oleorresina de chile habanero (Capsicum chinense) con β-ciclodextrina

Microencapsulation by molecular inclusion technique was applied by using β-cyclodextrin to reduce the degradation of carotenoids and capsaicin present in the habanero chili oleoresin. The molecular inclusion complex was prepared in the proportions 20:80 and 30:70 oleoresin:β-cyclodextrin, respectively, and stored for 5 weeks in a range of aw = 0.103–0.765 at 25, 35 and 45 °C, determining weekly total carotenoid contents (UV-Vis) and capsaicin (High Performance Liquid Cromatography (HPLC)). The molecular inclusion complex in the ratio 30:70 stored at 25 °C had a greater retention of total carotenoids and capsaicin at aw = 0.536 and 0.765, respectively, showing the highest shelf life values (5.92 and 5.68 weeks) and activation energy (−7618 and −6104 cal/mol·K) and the lowest values for the degradation constant (0.04 and 0.02 week−1), both processes carried out by a first-order kinetics.

PRODUKSI METABOLIT SEKUNDER STEVIOSIDA PADA KULTUR KALUS STEVIA (Stevia rebaudiana Bert. M.) DENGAN PENAMBAHAN ZPT 2,4-D DAN PEG (Polyethylene Glykol) 6000 PADA MEDIA MS (Murashige &amp; Skoog)

&lt;p class="Default"&gt;&lt;em&gt;Stevia&lt;/em&gt;&lt;em&gt; rebaudiana is a member of the Asteraceae family, produce steviol glycosides (steviosida, rebaudiosida A, B, C, D, E and dulcosida A) which can be used as food additives such as food flavoring or sweetener in nutritional supplements. This study aims to determine the concentration of 2,4-D combination and PEG 6000 were effective in increasing the production of secondary metabolites in callus of stevia (Stevia rebaudiana Bert. M) in vitro. PEG 6000 is a way to manipulate media in vitro to increase secondary metabolite. &lt;/em&gt;&lt;/p&gt; &lt;p class="Default"&gt;&lt;em&gt;This research used&lt;/em&gt;&lt;em&gt; Completely Randomized Design (CRD) with 12 factorial combination with three replications. The first factor is the provision of plant growth regulator 2,4-D (1 mg / L, 2 mg / L, and 3 mg / L) and the second factor is the provision of PEG 6000 (0 mg / L, 5 mg / L, 15 mg / L, and 25 mg / L). The emerging callus (day), percentage (%) of explants callus (g), weight of callus, callus morphology (texture and color of the callus), and secondary metabolites steviosida were measured. Data were analyzed by analysis of variance (ANOVA) two way and to find a significant difference test Duncan's Multiple Range Test (DMRT) at 5% significance level. Steviosida secondary metabolites were measured using High Performance Liquid Cromatography (HPLC).&lt;/em&gt;&lt;/p&gt; &lt;em&gt;The results showed that the combination treatment of 1 mg / L 2,4-D and 25 mg / L PEG 6000 is a combination of the most efficient way to get the amount of secondary metabolites steviosida 4.792 mg / g. Observations callus morphology (texture and color of the callus) showed that the compact callus textured and colored brown due to osmotic stress of PEG 6000 has a high content of secondary metabolites steviosida&lt;/em&gt;

Pre-concentration of ultra-trace furan in beverage samples and its determination by high performance liquid cromatography

Background Furan has been considered to be toxic and carcinogenic. In this research, a new method was applied for the pre-concentration of furan in beverage samples followed by high-performance liquid chromatography-ultraviolet detection (HPLC-UV) determination.

ATM Gene Alterations in CLL Patients Induce Gene Profile Clusters and Predict Disease Progression.

Chronic lymphocytic leukemia (CLL) presents a highly variable clinical course, with some patients surviving for many years without requiring treatment, while others have rapidly progressing disease, require aggressive treatment and show a short life expectancy. Several biological features of the leukemic cells - the mutational status of the immunoglobulin (Ig) heavy (H) chain variable (V) genes, cytogenetic alterations, ZAP-70 and CD38 antigen expression, p53 dysfunctions – bear prognostic value and allow to stratify patients into risk categories. The deletion of the chromosome region 11q22–q23 that occurs in 10–20% of cases represents the second most common genetic abnormality in CLL and defines a subgroup of patients characterized by advanced progressive disease and poor survival. The ATM (ataxia telangiectasia-mutated) gene is located in this region and several studies suggest that the 11q deletion results in ATM gene inactivation. The ATM gene consists of 66 exons, 62 (5–66) of which are coding exons. The ATM protein is a nuclear serine/threonine kinase of 350 kDa induced by chromosomal double-strand breaks that arise endogenously or after exposure to DNA-damaging agents, including ionizing radiations and drugs. It protects the integrity of the genome in several ways: it regulates the arrest of the cell cycle at the G1/S and G2/M phases to prevent the processing of damaged DNA; it activates DNA repair pathways and induces apoptosis if the DNA damage cannot be repaired. In the present study we examined the status of the ATM gene by DHPLC (Denaturing High Performance Liquid Cromatography) in a series of untreated CLL patients studied at the Division of Hematology, “Sapienza” University of Rome. In addition, a multiplex gene dosage analysis of the ATM gene was performed by MLPA (Multiplex Ligation Probe Amplification) in all patients. The results obtained have been correlated with the molecular status of the IgVH genes, the presence of cytogenetic abnormalities, ZAP-70 and CD38 expression, p53 mutations, and with the gene expression profile. Mutational screening of the ATM gene identified mutations in 8 of the 57 CLL patients studied (14%): 6 missense, 8095C>T (Pro2699Ser), 8071C>T (Arg2691Cys), 2476A>C (Ile826Leu) and, in 3 patients, 1435G>T (Asp479Tyr); 1 frameshift: 2502insA; 1 splicing mutation: IVS29+5G>A. In addition, 14 different variants and polymorphisms of unknown functional significance were found. The 8 ATM mutated cases showed the following features: 6 were IgVH unmutated, 4 were ZAP70+, 5 were CD38+, 4 harbored a 13q14 deletion, only 1 patient showed a 17p13 deletion and 2 a 14q32 deletion; furthermore, 2/8 patients showed a p53 gene mutation; none showed the 11q deletion. MLPA analysis identified 6 patients with 11q deletion and all of them showed at least 20% of cells positive for the 11q23 deletion evaluated by FISH; only 1 case showed a 17p13 deletion. In these cases, the IgVH gene was always unmutated and ZAP70 was positive; 4 cases were also CD38+. ATM gene mutated and deleted CLL cases showed a peculiar gene profile characterized by the up-regulation and down-regulation of genes involved in apoptosis and DNA repair function. On the contrary, no gene profile difference was found in patients carrying ATM gene polymorphisms. Patients with ATM gene mutated and deleted showed a short time to treatment, 23 and 19 months respectively. The results of this study indicate that ATM gene alterations - mutations or deletions - account for 24% of untreated CLL patients, are associated with a defined gene profile and are characterized by a poor prognosis. It is important to underline that these patients have been evaluated before any treatment and that ATM mutations have been found in the absence of 11q23 deletions. ATM alterations appear to represent the most frequent genetic abnormality with unfavorable prognostic implications in CLL and should be investigated prior to initiating therapy in order to plan an appropriate treatment algorithm.

Estudo da degradação do fármaco Nabumetona por fotólise direta

The present work aims to study the degradation of Nabumetone through direct photolysis. Solutions of Nabumetone in ethanol (20 mg/mL) were prepared and divided in quartz cuvettes with teflon lids. These were placed in the photolysis cabinet at 35oC. The photodegradation quantifications were analyzed in High Performance Liquid Cromatography (HPLC); after 47 days of photolysis the sample degradation was 67%, after 73 days 88.5% and after 111 days 89.5%. Spectrophotometers determinations (240 to 360 nm) were accomplished after 28, 47 and 73 days of photolysis. The photoproducts were separate for HPLC and analyzed by Gas Cromatograph coupled to Mass Spectrometer (GC-MS). The analysis in GC-MS of the Nabumetona photolyseded for 111 days allowed the suggestion of two substances.

Quantificação de 5-metiltetrahidrofolato no processamento e conservação de vinhos de uvas viníferas e híbridas

Folates are a class of vitamins that have been rediscovered in recent decades because of their association with various metabolic processes in the human organism. The main sources of folates described the scientific literature are vegetables, cereals and yeasts. The purpose of this study was to quantify 5-methyltetrahydrofolate (5-methyl-THF) in wines during wine production and aging. Red wines made from Cabernet Sauvignon, Merlot, and Pinot Noir wine grape varieties, and from Isabel (red) and Niagara (white) non-wine grape varieties were analyzed. The samples were analyzed at the beginning of fermentation, at the end of alcoholic and malolactic fermentation, and periodically at 4, 7, 12 and 24 months of age. High Performance Liquid Cromatography was used to separate, identify and quantify the folates. The results showed that the levels of 5-methyl-THF increased considerably during fermentation and continued to increase until the end of malolactic fermentation. The levels remained stable over a period of 3 to 6 months in the white wines and for 1 to 2 years in red wines, depending on the variety. The red wines proved to be a good source of 5-methyl-THF.

Hop as an Interesting Source of Resveratrol for Brewers: Optimization of the Extraction and Quantitative Study by Liquid Chromatography/Atmospheric Pressure Chemical Ionization Tandem Mass Spectrometry

Nowadays, hop is used almost exclusively by brewers for bitterness and flavor. Although hop polyphenols have been widely studied in the past decade for their antioxidant activity in the boiling kettle, very little is known about their real impact on health. The discovery of resveratrol in hop pellets highlights the potential health-promoting effect of moderate beer consumption. Here, we have optimized a quantitative extraction procedure for resveratrol in hop pellets. Preliminary removal of hydrophobic bitter compounds with toluene and cyclohexane at room temperature allows 99% trans-resveratrol recovery by ethanol:water (75:25, v/v) solid/liquid extraction at 60 degrees C. Reverse phase liquid chromatography proves an excellent means of separating isomers. In addition, we have compared two mass spectrometry ionization methods-atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI)-in both the positive and the negative modes. On the basis of standard additions applied with the optimized extraction procedure and reverse phase high-performance liquid chromatography-APCI(+)-tandem mass spectrometry, it appears that Tomahawk hop pellets (T90, harvest 2002) contain 0.5 ppm trans-resveratrol, 2 ppm trans-piceid, no cis-resveratrol, and 0.9 ppm cis-piceid.

Tandem action of exercise training and food restriction completely preserves ischemic preconditioning in the aging heart

Ischemic preconditioning (IP) has been proposed as an endogenous form of protection against ischemia reperfusion injury. IP, however, does not prevent post-ischemic dysfunction in the aging heart but may be partially corrected by exercise training and food restriction. We investigated the role of exercise training combined with food restriction on restoring IP in the aging heart. Effects of IP against ischemia-reperfusion injury in isolated hearts from adult (A, 6 months old), sedentary ‘ad libitum’ fed (SL), trained ad libitum fed (TL), sedentary food-restricted (SR), trained- and food-restricted senescent rats (TR) (24 months old) were investigated. Norepinephrine release in coronary effluent was determined by high performance liquid cromatography. IP significantly improved final recovery of percent developed pressure in hearts from A (p<0.01) but not in those from SL (p=NS) vs unconditioned controls. Developed pressure recovery was partial in hearts from TL and SR (64.3 and 67.3%, respectively; p<0.05 vs controls) but it was total in those from TR (82.3%, p=NS vs A; p<0.05 vs hearts from TL and SR). Similarly, IP determined a similar increase of norepinephrine release in A (p<0.001) and in TR (p<0.001, p=NS vs adult). IP was abolished by depletion of myocardial norepinephrine stores by reserpine in all groups. Thus, IP reduces post-ischemic dysfunction in A but not in SL. Moreover, IP was preserved partially in TR and SR and totally in TR. Complete IP maybe due to full restoration of norepinephrine release in response to IP stimulus.

Conteúdo de carotenos e provitamina A em frutas comercializadas em Viçosa, Estado de Minas Gerais

This work aimed to evaluate the contents of carotene (&alpha;, &beta;) and the value of vitamin A of fruits commercialized in local markets and fair of Viçosa (MG). Ten fruits were analyzed, originated of three local markets and three spot of the fair. The carotenoids extraction was accomplished with acetone, followed by transfer for petroleum ether. The contents of &alpha; and &beta;-carotene were analyzed by high performance liquid cromatography (HPLC). The &alpha;-carotene was found only in starfruit and papaya (cv. Formosa). &beta;-carotene was present in all the samples. Except for plum, there was no significant difference among the content of carotenoids of fruits from the local markets and fair. Thus, the fruits analyzed are good provitamin A sources and contribute with a percentage important in the adequacy of vitamin A for adult and children

IDRD2 TaqIA polymorphism is associated with urinary homovanillic acid levels in a sample of Spanish male alcoholic patients.

The TaqIA1 allele of the dopamine receptor gene D2 (DRD2) has been associated with alcoholism, as well as with other addictive behaviours. The exact nature of how the presence of this allele can be a vulnerability factor in the development of alcoholism remains unclear. In this study we found that the presence in the DRD2 genotype of the TaqIA1 allele in Spanish alcoholics is associated with higher levels of urine homovanillic acid (HVA) when compared to patients homozygous for the TaqIA2 allele. A sample of 142 Spanish male alcoholic patients was split into 2 groups on the basis of the presence or absence of the A1 allele in their genotype. The urine sample was analyzed by high performance liquid cromatography (HPLC), and the concentration of homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA) and vanilylmandelic acid (VMA) was determined. We found a statistical difference in the concentration of HVA between the groups, that suggests this polymorphism could be related to the variance of urine HVA levels.

Estudo comparativo da produção de metabólitos secundários em cultura de células e na planta in natura de Gomphrena globosa (Amaranthaceae)

The culture of calluses of Gomphrena globosa starting from segments foliate was established in half containing combinations of the phytoregulators auxina/citocinina. Identified secondary metabolites through the phytochemistry of the plant in natura were used as patterns in analyses for high performance liquid cromatography and gas cromatography of extracts of the culture. The comparative study revealed that the calluses were capable to produce some metabolite synthesized by the plant in natura.

Evaluation of circulating levels and renal clearance of natural amino acids in patients with Cushing's disease.

Although the hypercortisolism-induced impairment of protein homeostasis is object of several studies, a detailed evaluation of the complete amino acid profile of patients with Cushing's syndrome (CS) has never been performed. The aim of the current open transversal controlled study was to evaluate serum and urinary concentrations as well as renal clearance of the complete series of natural amino acids and their relationship with glucose tolerance in patients with Cushing's disease (CD). Twenty patients with CD (10 active and 10 cured) and 20 sex- and age-matched healthy controls entered the study. Measurement of serum and urinary levels of the complete series of natural amino acids was performed in all patients analyzed by cationic exchange high performance liquid cromatography (HPLC) after 2 weeks of a standardized protein intake regimen. The renal clearance (renal excretion rate) of each amino acid was calculated on the basis of the serum and urinary concentrations of creatinine and the specific amino acid. Fasting glucose and insulin levels, glucose and insulin response to standard glucose load, insulinogenic and homeostasis model insulin resistance (Homa-R) indexes were also evaluated and correlated to the circulating levels and renal clearances of each amino acid. Significantly higher serum (p<0.01) and urinary (p<0.05) levels of alanine and cystine, lower serum and higher urinary levels of leucine, isoleucine and valine (p<0.05) and higher renal excretion rates of leucine, isoleucine and valine (p<0.01) were found in patients with active CD than in patients cured from the disease and in controls. No difference was found between cured patients and controls. Creatinine clearance was similar in active and cured patients and in controls. In patients with active CD, urinary cortisol levels were significantly correlated to urinary cystine levels (r=0.85; p<0.01) and renal excretion rate of leucine (r=-0.76; p<0.05), isoleucine (r=-0.76; p<0.05) and valine (r=-0.66; p<0.05). Fasting blood glucose levels were significantly correlated to serum alanine levels (r=0.70; p<0.05). Although Homa-R was significantly correlated to BMI in active patients (r=0.74 p<0.05), it was not correlated to amino acid levels. In conclusion, the results of the current study demonstrate that patients with CD have significant changes in serum and urinary concentration of several amino acids and changes in renal clearance of some specific amino acids. Normalization of cortisol levels restored the amino acid profile.